Conceptual Physics (12th Edition)

by
Hewitt, Paul G.

Published by
Addison-Wesley

ISBN 10:
0321909100

ISBN 13:
978-0-32190-910-7

Chapter 13 - Think and Explain: 64

Answer

Designs in very tall buildings include sections of horizontal piping, to avoid having a long vertical drop. Sewage is allowed to drop through small vertical segments. It comes to a temporary stop at the horizontal sections, flows horizontally, then continues onward to the next short vertical drop.
(source: www.asee.org/public/conferences/1/papers/2739/download)